Waters 2489 - Operating the Detector in Dual Wavelength Mode

3-32 Preparing the Detector
2. Enter the wavelength and sensitivity on the absorbance screen, as well
as any secondary parameters and timed or threshold events.
See also:
• Figure “Secondary functions of the absorbance screen” on page 3-18
• Table titled “Primary and secondary function (method) parameters”
on page 3-19 through Table titled “Threshold events “To”
parameters” on page 3-39
3. To select a second sensitivity setting while in single wavelength mode,
press A/B and enter the appropriate AUFS on the channel B screen.
A single wavelength is tracked on channel A, allowing you to use
channel B to monitor absorbance with an alternate AUFS setting, or to
make the primary absorbance measurement using a specific AUFS on
channel A.
Example: While operating in single wavelength mode, set an AUFS of
2.0000 on the second channel. This provides 1.000 V/AU on the channel
B 2-V output.
The detector automatically engages the second order filter for all
wavelengths > 370 nm.
Operating the detector in dual wavelength mode
You can operate the detector with expanded chart out selections using dual
wavelength mode. In addition to absorbance offered with single wavelength
mode, dual wavelength offers the following functions:
• Absorbance (A and B)
•MaxPlot
• RatioPlot (A/B)
• Difference plot (A-B)
Section “Primary and secondary functions” on page 3-14 and the Table titled
“Primary and secondary function (method) parameters” on page 3-19 explain
these functions and their default and operating parameters in detail.
Caution: Changing the sensitivity (AUFS) setting affects the 2-V output.